Obesity and physical activity have been associated with decreased risk and improved outcomes for multiple cancers. In the US, childhood obesity is increasing while physical activity levels decline as children age. Since both track strongly into adulthood, the risk of subsequent obesity and presumably cancer in adulthood is increased. As a result, preventing childhood obesity and improving physical activity have been selected as major public health goals to reduce the risk and sequelae of obesity and cancer in the US. Walking to school is a national health objective of Healthy People 2010, and is consistent with the American Cancer Society's recommendation for children to engage in at least 60 minutes per day of moderate to vigorous physical activity. Walking to school is associated with 24-40 more minutes of moderate to vigorous physical activity per day. Increasing child pedestrian activity could increase the risk of injuries; however, walking with an adult reduced this risk by almost 70%. A walking school bus (WSB) addresses both physical activity and safety concerns by providing a period of physical activity supervised by several responsible adults and teaching opportunities around pedestrian safety skills on the way to and from school. Randomized controlled-studies are lacking on the impact of WSBs on children's mode of school transport, pedestrian safety, daily physical activity, and health. We seek to help fill this important gap. The goals of this research plan will be 1) to determine socio-demographic predictors of student participation in the WSB, 2) to evaluate the impact of a WSB program to decrease parental barriers to allowing their children to walk to and from school, to increase pedestrian safety behaviors, to increase walking to school, to increase daily moderate to vigorous physical activity, and to decrease weight gain in 4th grade students, and 3) to gain experience in implementing a WSB program with parent volunteers and determine parental acceptability and participation. Our specific aims include: (1) To conduct a longitudinal cohort study of 4th grade students and their parents to determine predictors of WSB participation related to socio-demographic data; (2) To successfully recruit 30 children per school from four public elementary schools (n=120) to participate in a pilot WSB intervention and conduct a 4-month pilot group randomized controlled trial to assess its impact in decreasing parents' perceived barriers to allowing their children to walk to and from school, to increase children walking to school, to increase child pedestrian safety behaviors, to increase daily moderate to vigorous physical activity, and to decrease weight gain in 4th grade students; and (3) To conduct a 4-month feasibility trial of the WSB program staffed by parent volunteers, collect process data, and conduct semistructured qualitative interviews with parents regarding acceptability. PUBLIC HEALTH RELEVANCE: The walking school bus (WSB) aims to increase students' walking to and from school, pedestrian safety, physical activity, and to decrease weight gain. The WSB will provide a targeted, population-based approach to address children's physical inactivity and the epidemic of childhood obesity. This in turn should lead to a substantial reduction in the risk of adult obesity and cancer. [unreadable] [unreadable] [unreadable]